<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        function primeNumber (num) {
            if(num==1){
                return false;
            }
            for(var i=2;i<num/2+1;i++){
                if(num%i==0){
                   return false;
                } 
            }
            return true;
        }
       while(true){
        var num1=prompt(`请输入一个数：`);
        alert(primeNumber(num1));
       }
    </script>
</head>
<body>
    
</body>
</html>